The Garamantes are described in the classical sources as nomads and brigands, and there will be some element of truth in this, but it must be noted that they were also the builders of a big city in the center of the desert, which has been found near modern Germa. The Greek researcher Herodotus of Halicarnassus (fifth century BCE) refers to them as great warriors, who still use chariots; later, the dromedary was domesticated, and they became caravan traders, who connected the Roman Mediterranean with Sub-Saharan Africa. Still, Rome had to fight several wars with the Garamantes.
It’s fascinating how a civilization could exist under the extreme desert conditions. Read more about them here, in my first real contribution to the Livius website in a couple of months.